DE945890C - Process for the production of composite fiber-particle boards - Google Patents

Description

Process for the manufacture of composite fiber-particle boards The invention relates to a process for the production of fiber-chipboard composite panels from vegetable matter Fiber stoles using a fiber liquor filled with coarse material mixed -is.

In the production of hardboard from vegetable fibers the pulp is usually made by sanding wood or by Grinding chemically pretreated wood particles, e.g. B. in equipped with steel disks Mills or by expressing wooden. fray under high steam pressures Nozzles, with an explosion-like relaxation and thus a defibration occurs. In all of these processes, the grown structure of the fiber verbaride is at least largely destroyed; it is broken down into individual ones that are separate from one another Fibers, sometimes cutting and shattering the fibers: instead of. These single fibers then, mostly with the addition of binders, e.g. B. curable phenol aldehyde resins, processed into hardboard through dewatering, shaping and compression in the heat, ivas usually started and carried out on Fourdrinier machines or in casting presses Pressing the fiber cake under high pressure and at high temperature in the final press is terminated. The hard plate, the hardness of which depends largely on the amount and type of added. Binder depends, with curable synthetic resins z. B. Additional amounts used by 5 @ 'o is then ready for manifold processing. To be influenced can the hardness, at least that of the surface, also by the fact that the finished plate with varnishes or hardening substances, e.g. B. synthetic resins, infiltrated will.

Another type of hard fiberboard can be cut through Injection of binders such. B. curable synthetic resins, coated wood chips, Sawdust or other small bodies of vegetable origin, e.g. B. Waste in which- Heat at very high pressures, e.g. B. of zoo kg / cm2. These procedures approach if large quantities of synthetic resins are used, the molding of synthetic resin molding compounds to plates, in which: the difficulty of even distribution of the in the plate shape there is poured material, which is the greater, the lower the proportion of synthetic resin is because of the flow of the material. when heated in the press then to a lesser extent: takes place and of that taking place at the pressing temperatures Hardening of the resin and gluing of the bevels - then too soon there is an overlap. To -so- the inconveniences are greater, as not only .an uneven thickness of the plate and the result is a bad surface, but rather: even badly grouted There are places because if the material accumulates, these places - at the expense of the less When sent, a significantly higher pressure is obtained, which otherwise leads to damage the press, yes, can lead to breakage. Even with very good distribution, Uneven strengths: the pressed plate hardly, or not at all, can be avoided.

The present invention follows a completely different way from the above-mentioned method, to prosecute so-called fiber-chip vegetables: chattering. For this purpose it is proposed according to the invention that the fiber liquor on the one hand has approximately 5% fiber slime. In addition to about 20% fiber material of size 3o to 70 ° Schoppier-Riegler, on the other hand, the remaining coarse material of 30 ° and less Schopper-Riegler to zii coarse fiber bundles of 10 ° Schopper-Riegler with a total size range of. 17 to z4 ° Schopper-Riegler and with mechanically untreated stuffy material, e.g. B. waste chips, combined by mixing and that the two components are dehydrated and converted under the effect of heat and pressure in the finished plate, the proportion of stuffy components between 20 and 70%, preferably. between 40 and 6o% of the mixture.

The lamination of chips into a fiber material; Flotte has already been suggested earlier, but only small amounts of chips should then be used, which have no influence on the physical and mechanical properties of the plates. can and only have a decorative effect. on the plate surface, the proposed gradation of the size ranges of the fiber content of the liquor with a, most favorable total grind size of -i7 to a4 ° Schopp-er-Riegler offers the main advantage that a favorable gradation is achieved not only with safety, but also the new effect that, on the one hand, the dewatering time is relatively short and, on the other hand, a fiber mixture is given such a great self-binding power. is that additions of binders such. ß Synthetic resins, largely reduced, if not even partially avoided entirely. If binders are added, e.g. B. in the usual. Amount, the advantage is obtained that the quality of the end product largely exceeds that of the fiber pulp masses obtained in the usual way and in this way the strength is increased considerably.

If binders should be added, the binder can be added both before and. even after the union of the two from pulp - on the one hand, stüklüg: em Material on the other hand existing components: made.

In contrast to the known processes for the production of hardboard about .ein water-fibrous sitoff pulp are -also, according to the invention, a whole certain pulp-water pulp pieces of pulp, e.g. B. chips, in a certain way and amount mixed in, which then penetrate the pulp more or less evenly and together with the pulp the drainage, molding and compaction processes run through. According to the invention, therefore, mechanically untreated are in principle - Waste shavings a ready-opened one. Pulp added in mixture, whereby the two. various wood substances, namely -on the one hand the pulp and on the other hand the untreated wood chips, are mixed together. This Mixing dry matter on the one hand can #nvilt wet fibers on the other hand in any desired ratio within the specified limits be achieved, @einje complete mixture is achieved.

The size composition is important for the ability to bind yourself of the pulp forming the pulp: When using a mass that contains too much coarse fiber bundles , contains, the binding force disappears more and more, and if it is too high Slime content. the drainage time increases to uneconomical levels up to several hours. Therefore for the realization of the invention this is proposed fiber mixture of great importance, which in addition to about 20 parts of of the order of 3o to 70 ° Schopper-Riegler contains about 5 parts fiber slime and as. Remaining fibers or fiber bundles down to approximately 10 ° Schopper-Riegler. These numbers: are of course variable within a certain range. It doesn't come on whether z. B. the parts from 3o to! 70 ° Schopper-Riegler now z. B. 17 or 2a% or whether the fiber sludge content is nine exactly 5%. Essential is the retention of a gradation of different sizes of the particles, namely that Presence of fibrous material on the one hand, not insignificant, on the other hand; elts. not like this: large amount, as there is an increased binding force with too long drainage times .being bought soot; and a substantial amount of particles is also essential from 3o to io ° Schopper- Riegler, i.e. coarse fiber bundles, and Finally, it is essential that the overall size range is approximately 17 to 24 ° Schopper-Riegler holds.

In the invention, one sees the advantage of using water pulp working process, namely the uniform charging of a mold that is made by The high water content of the pulp is selected, and the resulting uniformity Thickness of the fiber cake, and on the other hand the advantage of those coated with binders Processes working with pieces of fiber material, namely ballast-free, cheap production and the ease with which the desired properties of the finished body can be adjusted, achieved by appropriate choice of type and amount of binder.

The proportionate amount of chips in the fiber-chip mixture can, for example 20 hTs 70t4, preferably 40 to 60%, of the total mass, the pulp expediently a freeness of at least 18, preferably 20 to 25 ", Schopper-Riegl @ er owns. As is well known, the dewatering speed decreases with increasing degree of grinding, while the bondability increases. If the chip portion of the total mass is 700, '0, so you can go higher with the grinding degree, about 40 ° Schopper-Riegler, because then the binding force for the raw chips is sufficient, while the large proportion of chips facilitates drainage promotes. The lumpy material can be mechanical. Or chemical or simultaneously mechanical and chemical pre-treatment for improvement its elasticity or to prevent rot later or to make it water-repellent close.

While the raw use of the chips is preferred, it can chemical and / or mechanical treatment are required, e.g. B. a damping with chemicals or Kocheng if the material used without such treatment does not have the desired elasticity. With the steaming or Kocheng one can also subject the chips to a mild chemical breakdown.

It is recommended that the chips with larger amounts of binding agents such. B. 20 0ö synthetic resin and / or i% paraffins to impregnate. It can also be drying oils or other substances, e.g. B. paints, use. Soaking, impregnating or coating, in addition to the usual gluing, is best done by brief immersion in a bath or by spraying. The type of impregnation agent, the method of impregnation and the amount applied must of course depend on the properties desired and is different with mixed chips than with layer-forming chips. It is coming also on the intended use of the new fiber-chipboard composite panels. Table pads must be treated differently than furniture panels and these again differently from floorboards. With the invention you have one. further scope for implementation desired properties of the panels.

In addition to the advantages shown, when adding chips to the water-pulp liquor achieved a considerable reduction in price, since Zumengwlg of about 50 or even 700'o of untreated, air-dry wood shavings for this portion Procedural costs are saved. Seed mill waste can also be mixed in Use chip components as required. The manufacture of a fiber-chip composite board As a result, it is in any case cheaper than making an equally thick one Layer from the known fiber pulp, the considerable additional process costs needed.

In addition, it is contained in the relatively coarse pieces Fiber bandage has a favorable effect and by adding binders it is still considerable can be improved. As a result one achieves with material made of soft woods Board properties that are otherwise only available in hardwoods. Even the irregular one Storage of the chips in the fiber structure has a similar effect to plywood consolidation cheap.

It should be noted that such a plate is like a board made of grown Wood can be machined, nailed, etc. As a chunky material In addition to chips and sawmill waste, untreated bark, raffia, chopped straw, Use leaves, bagasse, sugar cane, bamboo, cotton fruit pods; n and the like. Advantageous the mixed-in or layer-forming chips can be wholly or partially colored which can also achieve very good effects.

Claims (7)

PATENT CLAIMS: i. Process for the production of fiber-chipboard composite panels from vegetable fibers using a fiber liquor which is mixed with coarse material, characterized in that the fiber liquor on the one hand has approximately 50.10 fiber slime and approximately aoo; o fiber material of the size 3o to 70 ' Schopper -Riegler and, on the other hand, the remainder contains coarse material of 30 ° and less Schopper-Riegler up to coarse fiber bundles of 10 ° Schopper-Riegler with a total size range of 17 to 24 '' and contains mechanically untreated lumpy material, e.g. B. waste chips, by mixing. combined and that the two combined components are dewatered and converted into the finished plate under the action of heat and pressure, the proportion of the lumpy components being between 20 and 700, preferably between 40 and 600, of the mixture. 2. The method according to claim i, characterized in that that binders are added to one or both of the components. 3. Method according to claim i or 2, characterized in that the fiber liquor substantial amounts, e.g. B. up to 70% of the total mass, admixed with sitückigem material will. 4. Procedure. according to claim 3, characterized in that the degree of grinding up to 40 '' Schopper-Riegler. 5. Procedure according to one of the Claims i to 4, characterized in that the lumpy material is a mechanical or is subjected to chemical or mechanical and chemical pretreatment for Improvement of its elasticity, for later rot prevention or to make it water-repellent close. 6. The method according to claim 5, characterized in that the chips groove larger amounts of binders, e.g. B. 2o% synthetic resin, be imprägTiemt. 7. The method according to any one of claims i to 6, characterized by the use of sawmill waste as a chip component to be used or layer-forming. Publications considered: Swiss Patent No. 238 848.